I use a green kitchen pad, the kind you use for dishes....no soap kind.
Toothbrush didnt' touch it. I had a sponge for the glass, but I'll look into the kitchen kind and see if I can clean it that way.
I use the same pads as Slug in post #4. Do not use these pads on your glass or acrylic tanks. It will scratch both. A friend used one washing my truck and it left scratches in the paint and on the glass. It will not hurt your glass heater though or prevent it from functioning the way that it should.
worked perfectly! Thanks again.
I use a toothbrush - weekly. Never gets too bad.
Plastic pot scrubbies work and don't scratch glass the way the Scotch Brite pads do.